The use of masonry block walls in construction is very popular. In order to construct a masonry block wall that has the necessary structural strength, the masonry block wall must be tied to an associated foundation or footing. When the foundation or footing for a masonry block wall is being prepared, reinforcing bars are placed in the footing. These reinforcement bars (known as starter bars) protrude from the concrete footing and are required to engage the masonry block wall. However, the starter bars are often not placed in the correct location in relation to the cavity in the masonry blocks of the masonry block wall.
Misaligned starter bars are a huge problem for a block layer. The block layer is often unable to bend or adjust the incorrectly placed starter bars coming out from the concrete footing. Accordingly, the starter bars are not in their correct position and do not line up with the vertical reinforcing bars that are placed in the masonry block wall. The starter bars being out of position and not aligning with the vertical reinforcing bars in the masonry block wall during wall construction will result in the wall not meeting the structural capacity as detailed in the engineering specification for the wall. In a worst case scenario, the entire wall, including the footing, will need to be demolished and rebuilt at substantial cost.
The majority of reinforced masonry block walls require starter bars (and vertical reinforcing bars) to be generally used at 400 mm intervals along the wall. The problem of misaligned starter bars is therefore a considerable inconvenience to the block layer because of the large number of starter bars in each wall construction.